Changing Planet

On the Hunt for Harvestmen

On his current expedition, Ronald Clouse ventures into the jungles of the Philippines to study harvestmen, or daddy-long-legs, of the order Opiliones. By collecting data for phylogenetic analysis, he hopes to learn more about the history of these creatures and the lands they inhabit.

The sun sets over a beach in Pandan, Panay Island. (Photo by Ron Clouse)

Tuesday night, May 14th, I arrived in Manila via Hawaii and Guam. Guam always looks small when coming from Hawaii, huge when coming from a long stay in the aptly named islands of Micronesia. I was met at the airport by project member Dr. Prashant Sharma, who has been here collecting on the island of Luzon since late April. He collected daddy-long-legs—I’ll call them by their arachnid order name of Opiliones, pronounced “OH-pill-ee-OH-nez,” from here on—in several locations previously unsurveyed for these interesting animals: Mt. Palay-Palay, southwest of Manila; Mt. Banahaw, southeast of Manila; Adams, in northern Luzon; and the beach resort of Pagudpud, also in the North.

Guam appears on the horizon during one leg of the plane ride. (Photo by Ron Clouse)
Guam appears on the horizon during one leg of the plane ride. (Photo by Ron Clouse)

That night we were joined by project member and PhD student Dave General, who will be joining us in the field later, and the next morning we went to the National Museum of the Philippines to meet with project members and museum researchers Perry Buenavente (who has made all the arrangements for this expedition!) and John Rey Callado. After final paperwork was completed, Prashant, Perry, John Rey, and I headed to the airport to fly to Panay Island, where we are now, preparing to collect in the forest near Pandan, far in the Northwest of the island. In a few hours we will leave for Sibaliw Research Station. To get there, we’ll climb about four hours from the coast into the forest at about 500-meters elevation. There we will be sifting leaf litter and collecting Opiliones for several days.

A street in the town of Pandan, Panay Island. (Photo by Ron Clouse)
A street in the town of Pandan, Panay Island. (Photo by Ron Clouse)

We are being helped with our arrangements in Panay by the Panay Eco-Social Conservation Project (PanayCon), formerly known as the Philippine Endemic Species Conservation Project. We visited their offices in the afternoon, and in the course of talking saw the homemade guns confiscated by the organization. Made from PVC pipe, plastic bottles, wood, and other materials, they are used to hunt various forest animals, including protected birds.

Perry Buenavente examines a confiscated homemade gun in a PanayCon office. (Photo by Ron Clouse)
Perry Buenavente examines a confiscated homemade gun in a PanayCon office. (Photo by Ron Clouse)

We are excited to be in Panay, especially this region, as it appears to have the chance of being continental in origin. Certain plant and animal taxonomic groups here (including certain Opiliones) resemble elements found on Palawan Island to the west, which is hypothesized to be a piece of the Chinese coastline that moved east to its present location as the South China Sea opened up 20–30-million years ago.

The Philippines may appear to be a cohesive archipelago with a single origin, but the islands arrive from different locations, formed by different processes, and in some cases single islands are composites of different terranes from different beginnings. Geologists hypothesize the origins of the islands based on various pieces of physical evidence gathered from the rocks and deposits here. Opiliones provide an excellent opportunity to test those hypotheses, as they have very poor dispersal abilities and are often distributed in regions due to the movements of the landmass on which they live.

Canoes line a beach in Pandan, Panay Island. (Photo by Ron Clouse)
Canoes line a beach in Pandan, Panay Island. (Photo by Ron Clouse)

The Opiliones least likely to disperse are in the group (brace yourself!) “Cyphophthalmi.” These small, thick-legged animals look like seeds in the leaf litter, and they are known from only three juveniles and one adult in the Philippines. Not coincidentally, they are known from islands that have had hypothetical continental origins, at least in part: Palawan and Mindanao. Continental landmasses have been above water for far longer than land originating as volcanoes from the sea floor, and they can drift around, connect and split from other landmasses, and carry animals reluctant or unable to cross open ocean. We will collect on Minadanao next month, but for now we are excited to see if there is evidence here on Panay of it once being connected to Palawan.

Watch more videos from this expedition

Read all posts by Ronald Clouse

Ronald Clouse investigates the histories of invertebrates found in the leaf litter. He works mostly with arthropods in the Indo-Pacific, especially harvestmen (daddy-long-legs) and ants. He also works with harvestmen in Brazil and the southern U.S., and he is interested in the processes by which we reconstruct history using DNA and morphology.
  • Lucinda Boyd

    Just finished your update from yesterday, and then given myself the treat of watching your “Jeepney” videos. I am impressed but as usual stunned with the casualness of non-USA traffic — bicycles, rickshaws, decorated Jeepneys, Japanese autos — all keep moving, somehow allowing for non-linear operations.
    That mountain and the rest station photograph so well that it feels like being there — maybe you need one fo the emergency blankets sold for auto use — think you stay warm wrapped in one. Cheers

  • I’m very happy you are enjoying the reports, Lucinda. The Jeepneys are works of art, and just when I think I have a photo or video of the ultimate specimen, a better one drives by. I didn’t plan on doing this, but in those videos, as you noticed, there are instances when you cringe at impending collisions, which miraculously never seem to occur. However, this weekend we were kindly helped by a friend who is an orthopedic surgeon on Luzon; the main source of his patients are motorcycle drivers, so this casualness does take it’s toll. Good idea on the blanket, to be followed from here on. My camping on Mt. Bulusan this weekend was very warm and cozy, despite being at 900 meters. This was mostly because with the rain shield down, and my large size, my little tent became a bit of a sauna. Wishing you the best.

  • Since I know a certain English teacher might be reading this, I’ll blame “it’s” on my iPad autocorrect! One of the great things about the Philippines is that for about $US 20, one can put a SIM card in an iPad and receive unlimited data via 3G service wherever there’s cell phone service, which is nearly everywhere.

  • Susan Bednarczyk

    I really enjoyed your kick-off video and have shared it extensively on Facebook with all of your East Coast fans at AMNH and North Carolina. Great set-up to the rest of the posts! Thanks!

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